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While the behavioral side of categorical perception in speech is al-ready well investigated, little is known concerning its underlying neural mecha-nisms. In this study, a computer-implemented neurophonetic model of speech production and perception is used in order to elucidate the functional neural mechanisms responsible for categorical perception. 20 instances of the model (˵virtual listeners/speakers″) underwent a speech acquisition training procedure and then performed behavioral tests, i.e. identification and discrimination experiments based on vocalic and CV-syllabic speech stimuli. These virtual listeners showed the expected behavioral results. The inspection of the neural organization of virtual listeners indicated clustering in the case of categorical perception and no clustering in the case of non-categorical (continuous) perception for neurons representing the stimuli. These results highlight a possible neural organization underlying categorical and continuous perception. [ABSTRACT FROM AUTHOR]

This paper investigates two types of questions. OBJECTS, challenging the interlocutor΄s assumption that information is shared, are biased towards a negative answer, whereas QUERIES, asking for new information, are generally neutral. In Bari Italian they are both produced with the same pitch accent. However, the height of the pitch peak tends to be greater in OBJECTS. To investigate the perceptual relevance of peak height in distinguishing between these two question types, we carried out a semantically motivated identification task, followed by a discrimination task, recording reaction times in both cases. Results show that listeners can categorically interpret utterances as QUERY or OBJECT on the basis of peak height only. However, their ability to discriminate between pairs of stimuli is poor, thus providing further evidence that categorical interpretation of intonation (like that of vowels) is possible in a labelling task, where listeners have to access linguistic knowledge, whereas it is not possible in a discrimination task, where listeners rely predominantly on psychoacoustic abilities. Results point to the necessity for including [high peak] in the phonology of this variety. [ABSTRACT FROM AUTHOR]